1. Field of Invention
The present invention relates to a back light module. More particularly, the present invention relates to a back light module of a liquid crystal display.
2. Description of Related Art
CRT display technology has been widely used for several decades. The advantages of CRT display are its excellent performance and low price due to mass production. However, the large size and high operation voltage thereof exclude CRT display from adapting to some applications.
In recent years, Flat Panel Display has been developed to achieve the same display performance as CRT display. An LCD (Liquid Crystal Display) panel is one type of Flat Panel Display technology that can be mass produced. The lightness and thinness thereof give LCD display a wide variety of uses, such as in PDAs (Personal Digital Assistants), notebook PCs, and other information appliances.
Because the liquid crystal can't emit light by itself, a backlight module is employed to provide a light source for the liquid crystal. In other words, the back light module provides brightness, light uniformity, and view angle. In mechanical features, the backlight module is also required to be thin, light, and shock resistant.
FIG. 1 illustrates a perspective view of backlight module for a conventional LCD. A rectangular backlight distributor 10 is equipped with four light pipes 15 at two sides. The four light pipes 15 are divided into two groups of two light pipes, respectively. This structure results in an LCD that is insufficiently thin and light.